Just looking at your pictures, it looks like there isn't any flux in the solder, or if there is, it's crap/insufficient. You do not want to skimp out on solder. I spent years soldering horribly, it wasn't until I discovered that the solder I was using was a POS and I actually bought something decent that everything turned around.

Trying to hand-solder fine pitch SMD chips without good flux is very difficult even for an expert. Personally, I like a liquid R or RMA (rosin) flux, applied with a small brush, as applied sparingly the residue does not need to be cleaned up, but many will swear by synthetic or rosin gel fluxes applied from a syringe with a needle. I don't like flux pens much for rework as the tip tends to get torn up on rough surfaces like existing joints. Whatever you do, don't use paste flux in a tub or tin from the hardware store as most such fluxes are far too aggressive and their residues will corrode the tracks off your board and the pins off your chip.

With flux, the surface tension of the solder acts to pull it back to the pin/pad area, breaking any bridges unless far too much solder was used. Simply applying flux to the pins and pads and reheating them several at a time with a freshly tinned and wiped bit, removing it outward with a dragging motion towards the tips of the pins should leave you with no bridges and, if there was an appropriate amount of solder present, with acceptable joints.

If you need to remove excess solder, wick it off with a fluxed fresh piece of wick. When cutting back the used end of the wick to get to fresh wick, always bend it to find how far the solder wicked up it and cut it back leaving a couple of mm, but no more, that has solder wicked into it at the end for better quicker heat transfer when you apply the iron to it and the joint. Wick oxidises readily and if its too old may be unusable. A year or so isn't a problem, but if its visibly tarnished or decades old its useless for fine work.

350 deg C, or maybe slightly hotter would be a good temperature to start with. 250 deg C is far too cold and 450 deg C is far too hot. Except under exceptional circumstances stay in the 315 to 375 deg C range. Cheaper irons with poorer thermal coupling to the tip or less power delivery tend to need a slightly higher setting within that range, as do many unleaded solders.

Search Dave's EEVBLOG videos for 'drag soldering' to find out how to do it right in the first place.

You have a severe lack of flux, just wet all the pins and the board with flux, then you just touch the tip of the iron after staining it and BAMM, its soldered, in the end drench in with IPA and its clean and shiny.Also, if it is for personal use, get some eutectic lead solder and avoid crappy lead free solder.

I use a liquid RMA flux in one of the cheap eBay squeeze bottles with the hypo needles on them. I squeeze the tip down until almost closed so it dispenses without going all over the place. Like Louis Rossman, I believe in that there is no such thing as too much flux. Really good solder is important. Kester 44 with 66 core, 63/37. Worth every penny.

I'm a noob as well, and with a generouse amount of flux I was able to solder some SOP-16's on my first go using the drag technique. I spent more time trying to line it up nicely and get the opposite corners tacked down so I could use both hands easily.

Also, with the resistors & caps I found it easier to solder when I used a footprint that was bigger than the part. The pads for the passives in your photo look like they'd be great for reflow soldering with paste, but a PITA for hand soldering.

I'm a noob as well, and with a generouse amount of flux I was able to solder some SOP-16's on my first go using the drag technique. I spent more time trying to line it up nicely and get the opposite corners tacked down so I could use both hands easily.

Also, with the resistors & caps I found it easier to solder when I used a footprint that was bigger than the part. The pads for the passives in your photo look like they'd be great for reflow soldering with paste, but a PITA for hand soldering.

I only had issues with one or two of the passives. Basically because I put them too close together!

Thanks for all the tips. I have ordered some flux and will see how that goes.

I'm a noob as well, and with a generouse amount of flux I was able to solder some SOP-16's on my first go using the drag technique. I spent more time trying to line it up nicely and get the opposite corners tacked down so I could use both hands easily.

Also, with the resistors & caps I found it easier to solder when I used a footprint that was bigger than the part. The pads for the passives in your photo look like they'd be great for reflow soldering with paste, but a PITA for hand soldering.

I only had issues with one or two of the passives. Basically because I put them too close together!

Thanks for all the tips. I have ordered some flux and will see how that goes.

Sent from my ONE A2003 using Tapatalk

Flux paste is the way to go I think with IC packages. It will hold the package in place for you while you get the first pins going.

I'm a noob as well, and with a generouse amount of flux I was able to solder some SOP-16's on my first go using the drag technique. I spent more time trying to line it up nicely and get the opposite corners tacked down so I could use both hands easily.

Also, with the resistors & caps I found it easier to solder when I used a footprint that was bigger than the part. The pads for the passives in your photo look like they'd be great for reflow soldering with paste, but a PITA for hand soldering.

I only had issues with one or two of the passives. Basically because I put them too close together!

Thanks for all the tips. I have ordered some flux and will see how that goes.

Sent from my ONE A2003 using Tapatalk

Flux paste is the way to go I think with IC packages. It will hold the package in place for you while you get the first pins going.

That would be me. I've never been fond of the cleanup required after using electronics grade paste fluxes. Non-electronics grade acid fluxes are just a disaster waiting to happen which is why I cautioned against hardware store flux.

Some of the electronics grade paste or gel fluxes may be no-clean in a production environment, but when prototyping, before applying power, you want the solvent to be fully evaporated from their residues leaving hard rosin which doesn't happen quickly if your flux left blobs of goop wherever you put it so you end up having to scrub supposedly no-clean flux off your board.

I also don't believe in using flux as an adhesive as I find tacking a corner pin, and reheating to tweak the alignment as required then tacking the opposite corner pin works well for me, and the more goop you put under a part the worse your cleanup problems.

However fluxes have improved since I learnt my skills so by all means give paste or gel fluxes a try. Louis Rossmann swears by Amtech flux NC-559-V2-TF and if it works for him repairing Apple notebook mainboards . . . However you should note that he has a swept frequency ultrasonic cleaner tank permanently setup for cleanup and if you don't have that sort of facilities, you'll be drastically increasing your solvent exposure if you need to clean flux residues off manually.

If you're doing many SMD, I'll suggest using a syringe of solder paste instead of solder wire.

Lay down dots of the solder paste, position the component, solder one corner pad, fine-tune alignment, solder the opposite corner, then move along each edge with the iron. Work your way around so the next pin pre-heats while you solder the current one. It takes very little time on each pin with this technique, which is kind to the chip, and the results are very clean.

For the resistors and caps, hold smaller ones in position with a dental pick while the first end is soldered, to keep them aligned.

I looked at your photos. This is a completly diferent technology. I have come across the problem on 2 computer related boards and a modem board. They cant be soldered using a simple soldering iron. It is wave soldered. The solder wount melt.

Killing a chip by overheating it isn't that easy. You can easily damage sensitive passives, plastic connector parts, but you'd lift the copper off the PCB much sooner than you could kill an integrated circuit.

I've done some pretty shitty solder jobs back when I was starting out, but I honestly can't recall ever killing a chip because I fiddled around with a soldering iron for too long.

Logged

<fellbuendel> it's arduino, you're not supposed to know anything about what you're doing<fellbuendel> if you knew, you wouldn't be using it

I'm a noob as well, and with a generouse amount of flux I was able to solder some SOP-16's on my first go using the drag technique. I spent more time trying to line it up nicely and get the opposite corners tacked down so I could use both hands easily.

Also, with the resistors & caps I found it easier to solder when I used a footprint that was bigger than the part. The pads for the passives in your photo look like they'd be great for reflow soldering with paste, but a PITA for hand soldering.

I only had issues with one or two of the passives. Basically because I put them too close together!

You did.Layout is crucial to success for hand population and soldering, it's preferable to populate a PCB with the passive devices first and still have enough room to solder the IC's etc later.When doing layouts keep in mind the method of PCB population AND access to components for any possible rework.